Suspended ceiling grid structure



Feb. 16, 1965 g c oy SUSPENDED CEILING GRID STRUCTURE Filed Jan. 23, 1962 FIG. 2.

FIG. 4.

FIG. 3.

INVENTOR. JOHN H. McCOY ATTORNEY United States Patent Ci" 3,169,614 SUSPENDED CEILING GRID STRUCTURE John H. McCoy, Radnor, Pa., assignor to National Rolling Mills Co., Malvern, Pa., a corporation of Pennsylvania Filed Jan. 23, 1962, Ser. No. 168,296 4 Claims. (Cl. 189-82) This invention relates to improvements in a suspended ceiling grid structure, and more particularly concerns improvements in a suspended ceiling grid structure adapted to support ceiling tiles or the like, and improvements in connecting means between the elements of the grid structure.

Although suspended ceiling grid structures have heretofore been provided, previous structures have had a number of disadvantages. Many of the previous ceiling structures required the use of connecting clips which had to be riveted or welded to the ends of the cross members.

Another conventional structure was provided with tabs on the end of the connecting clips and the tabs had to be twisted to attach the cross members securely to the main beam. This twisting consumed time on installation of the suspended ceiling grid structure, and was also disadvantageous in that it was diflicult to disassemble when the cross members and ceiling tiles were being removed to gain access to the space above the suspended ceiling, for example, to service apparatus such as plumbing or airconditioning.

Previous ceiling-grid cross members have required the use of two types of cross members, one having the twisttab and another having an overhang type of connector, with the difierent types being positioned alternately so that the center lines of the cross members would be in alignment. 7

One of the objects in suspended ceiling grid structures is to position the bottom flanges of the cross members absolutely flush with the bottom flanges of the main beam. In previous devices, the twist-tabcould be turned so much that it would cause the, bottom flanges of the cross'member to ride upwardly so that it would not be flush with the bottom flanges of the main beam.

Accordingly, it is an object of this invention to provide a suspended ceiling grid structure which overcomes the foregoing problems and disadvantages.

.It is another object of this invention to provide a suspended ceiling grid structure which is easy to install and easy todisassemble when it" is desired to gain access to the'space above the suspended ceiling.

It is another object of this'invention to provide a cross member which has a universal type connector, thus eliminating the necessity of manufacturing and stocking two difierent types, such as the twist-tab type and the overhang type..

It is another object of this invention to provide 'connecting means between cross and main members which gives strength and rigidity to the grid structure, and provides for alignment of the center lines of the cross' of the main beam.

It is another object to provide a suspended ceiling grid structure which is easier and more quickly installed, and

which is less expensive to manufacture.

Other objects and advantages of this invention, includ- 3,169,514 Patented Feb. 16, 1965 ing its simplicity and economy, will further become apparent hereinafter and in the drawings, in which:

FIG. 1 is a fragmentary view in perspective of a suspended ceiling grid structure constructed in accordance with this invention;

FIG. 2 is a view in section taken as indicated by the lines and arrows 22 which appear in FIG. 1;

FIG. 3 is a view in section taken as indicated by the lines and arrows 33 which appear in FIG. 1; and

FIG. 4 is a view in section taken as indicated by the lines and arrows 4-4 which appear in FIG. 1.

Although specific terms are used in the following description for clarity, these terms are intended-to refer only to the structure shown in the drawings and are not intended to define or limit the scope of the invention.

'Turning' now to the specific embodiment ofthe invention selected for illustration in the drawings, there is shown a suspended ceiling grid structure adapted to support ceiling tiles 11 which comprises a plurality of main beams 12 arranged in spaced-apart, substantially parallel relationship, across Ts 13 which connect adjacent main -Each main beam 12 has an inverted-T shape, and includes a central fin 15 with a rolled bead 16 at the top and a pair of oppositely disposed flanges 17 at the bottom. A capping 18 is mounted on flanges 17.

Cross Ts 13 are also of inverted-T construction and each includes a central fin 21, flanges 22extending from the bottom of the central fin'21, and capping 23 mounted on flanges 22. Lockingtongues 24,- 25 are formed in tegrally with cross T 13 and extendin opposite directions from each end of the 'cross T at substantially right angles to cross T central fin '21. Ribs 26 give strength to the ends of cross T 21. Each tongue 24, 25 has a locking hole 27 and a stop recess 28 formed therein.

A pair of facing, horizontally aligned holding tabs 31 are stamped in central fin 1'5of the main beams 12 for holding locking tongues 24 or 25. Holding tabs 31 prevent vertical movement of cross Ts 13. It is to be noted that cross Ts 13 have hanger holes 32 formed therein from which wire hangers 14 extend upwardly to aid in supending the ceiling grid structure. I

Holding tabs 31 are provided with entrance portions 33 which are flared outwardly from main member fin 21 for easy insertion therein of the lockingtongues 24' or25. Positioned 1n main beam central fin 15 forwardly, in

the insertion path of the locking tongues, from the exit insertion path of the locking tongues, is a stop lug 35 which projects outwardly from main beam central fin 15 to contact stop recess 28 of its associated locking tongue to aid in positioning the tongue in its fully inserted position. Stop lug 35 stops the horizontal travel of its asso ciated locking tongue and also aids tabs 31 in preventing the locking tongue from canting and assuming a position away from'the horizontal.

Hanger holes36 are formed in main beam central [in 15 and wire hangers 14 extend upwardly therefrom to support the ceiling grid structure.

Inoperation, main beams 12 are suspended from the ceiling, and cross Ts 13 are snapped into place in positive manner by inserting locking. tongues 24 and 25 in theirassociated holding tabs 31. Locking hole 27 makes an audible click as it snaps into place over locking dimple 34, a sure, mistake-proof signal to the installer that tongues 24 and 25 are inserted properly.

The advantages of the suspended ceiling grid structure constructed in accordance with the invention are many. It is easier and quicker to install by merely snapping the locking tongues 2 4 and 25 into place than to turn the twist tabs of previous devices. i

The space above the suspended ceiling is much more accessible, since it is much easier to remove the cross T s by merely withdrawing the locking tongue '24, 25 from their associated holding tabs 31, instead of trying to unturn a twisted tab with a pair of pliers. Sometimes in tryin to unbend the twist ,tab the vtab would break oh, and if the broken cross member .was later replaced in the grid system, it would not be securely positioned therein. Anew connector would have to be riveted onto the cross member so that it could beattachedto the main beam.

In manufacturing main beams 12, the stamping of'holding tabs 31 does not require a ,separate operation since hanger holes 36 must be stamped in main beam fin 21 anyway. Hanger holes 36 and holding tabs 31 are stamped in cross T central fin 21 in the same operation.

Cross Ts 13 are universal, and eliminate the necessity of manufacturing and stocking two types of cross members such as the twist-tab type and the overhang type. Locking tongues 24 and 2 are preferably madeof sheet steel, which is a flexible material, and locking dimples 34 project outwardly to make good contact with the somewhat flexible locking tongues 24, and hold them and cross Ts 13 firmly and positively in place. Besides insuring frictional contact with locking tongues 24, 25, locking dimples 34 also add' strength to main beam 12 because of the cold Working of the metal involved in stamping the dimples.

Added strength and rigidity are-given .to thegrid structure because locking tongues 24 and25 extend'in opposite directions. This also permits the center lines of cross Ts 13 to be in alignment so .as to obtain a continuous run of cross Ts 13. e

The location of holding tabs 31 in: cross T centralfin 21 is such that cross I bottom flanges 22 are flush with the bottom flanges 17 of main beams 12, and also flush with each other.

In the previous twist-tab-device, the tab could be turned so much that it would cause the bottom flanges of i the cross T to ride upwardly and it would therefore not be flush with the bottom flanges of the main beam. The in staller, if he were doing a fast job or was slopping about doing it, would-sometimes tighten the twist-tabs too tightly and would have some cross Ts riding high and some riding low and some riding-atanangle so that the cross T bottom flanges would not be flush with -the main beam bottom flanges;' i

In the present invention, there is no chance of turning anything during the installation procedure that would make the cross T bottom flanges ride up or down. The

, cross T just moves in a horizontal'fashion into engagement with the main beam and the locking tongues 24 and 25 make precise connection with holding tabs 31 so that they are properly positioned in a vertical sense. The

integrally formed with the'cross Tnjcentral fin 21, and the separate riveting or'welding operation required to attach the connecting clips of previous devices iseliminated.

It is to be understood that the form of the invention herewith shown and described is to be taken as a presently preferred embodiment. Various changes may be made in the shape, size and arrangement of parts. For example, equivalent elements may be substituted for those illustrated and described herein, parts may be reversed, and certain features of the invention may be utilized independently of the use of other features, all without departing from the spirit or scope of the invention as defined in the sub-joined claims.

The claimed invention is:

1. A suspended ceiling grid structure adapted to support ceiling tiles or the like, comprising a plurality of mainbeams arranged in spaced-apart, substantially parallel relationship, each main beam having a central fin and oppositely disposed bottom flanges, cross Ts connecting adjacent main beams and having a central fin and oppositely disposed bottom flanges, a locking tongue extending from each end of said crossTs in opposite directions at substantially right angles from the cross T central fin, a pair of facing, parallel, horizontally disposed, vertically aligned holding tabs formed in the central fin of the main beam, the distance between the base portions of said tabs being substantially equal to the width of the locking tongues, thereby holding said locking tongues and preventing vertical movement of the cross Ts, said tabs having an entrance portion which is flared outwardly from said main beam fin for easy insertion therein of the lockingtongue, said'main beam and cross Ts having hanger holes formed therein from which extend wire hangers, each tongue having a locking hole formed therein, alock ing dimple formed in the central fin of said main beams which registers with and snaps into said locking holes when the locking tongue is fully inserted into its associated holding tabs, and a stop lug projecting from the central fin of said main beams, each tongue having a stop recess formed in its end for contacting its associated stop lug to aid'in positioning said tongue in its fully'inserted positron.

2. Connecting means between ceiling-grid inverted-T main and 'cross members disposed at right angles to each other and having upright central fins and bottom :horizontal flanges, comprising a locking tongue extending from each end of said cross members in opposite directions at right angles to the cross member fin, and a pair a of facing, parallel, horizontally disposed, vertically aligned holding tabs formed inv the central tin of the main members, the distance between the base portions of said tabs being substantially equal .to the width of the locking tongues, thereby holding one of said locking tongues, said tabs. having an entrance portion which is flared outwardly from the main member fin foreasy insertion therein of the locking tongue.

. 3. Connecting means between ceiling-grid inverted-T main and cross members disposed at right angles to each other and having upright central fins and bottom hart zontal flanges, comprising a locking tongue extending from each end of said cross members in opposite directions at right angles to the cross member fin, a pair of facing, parallel','horiz ontally disposed, vertical aligned holding tabs formed in the central fin of the main members, the distance between the base portions of said tabs being substantially equal to the width of the locking tongues, thereby holding one of said locking tongues, said tabs having an entrance portion which is flared outwardly from the main member fin for easy insertion therein of the locking tongue, each tongue having a locking hole formed thereimand a locking dimple formed in the central fin of said main member which registers with and snaps into said locking hole when the locking tongue fully inserted into its associated'holding tabslf 4.]Co'nnecting means between ceiling-grid inverted-T main and cross members disposed'at right angles to each other and having upright central fins andfb ottom hori.--

zontal flanges, comprising a locking tongue extending from each end of said cross members in opposite directions at right angles to the cross member fin, a pair of facing, parallel, horizontally disposed, vertically aligned holding tabs formed in the central fin of the main members, the distance between the base portions of said tabs being substantially equal to the width of the locking tongues, thereby holding one of said locking tongues, said tabs having an entrance portion which is flared outwardly from the main member fin for easy insertion therein of the locking 10 said main member, each tongue having a stop recess formed in its end for contacting its associated stop lug to aid in positioning said tongue in its fully inserted position.

References Cited in the file of this patent UNITED STATES PATENTS 1,757,141 Raster May 6, 1930 2,627,948 Farr Feb. 10, 1953 2,896,752 Wilde July 28, 1959 

1. A SUSPENDED CEILING GRID STRUCTURE ADAPTED TO SUPPORT CEILING TILES OR THE LIKE, COMPRISING A PLURALITY OF MAIN BEAMS ARRANGED IN SPACED-APART, SUBSTANTIALLY PARALLEL RELATIONSHIP, EACH MAIN BEAM HAVING A CENTRAL FIN AND OPPOSITELY DISPOSED BOTTOM FLANGES, CROSS T''S CONNECTING ADJACENT MAIN BEAMS AND HAVING A CENTRAL FIN AND OPPOSITELY DISPOSED BOTTOM FLANGES, A LOCKING TONGUE EXTENDING FROM EACH END OF SAID CROSS T''S IN OPPOSITE DIRECTIONS AT SUBSTANTIALLY RIGHT ANGLES FROM THE CROSS T CENTRAL FIN, A PAIR OF FACING, PARALLEL, HORIZONTALLY DISPOSED, VERTICALLY ALIGNED HOLDING TABS FORMED IN THE CENTRAL FIN OF THE MAIN BEAM, THE DISTANCE BETWEEN THE BASE PORTIONS OF SAID TABS BEING SUBSTANTIALLY EQUAL TO THE WIDTH OF THE LOCKING TONGUES, THEREBY HOLDING SAID LOCKING TONGUES AND PREVENTING VERTICAL MOVEMENT OF THE CROSS T''S SAID TABS HAVING AN ENTRANCE PORTION WHICH IS FLARED OUTWARDLY FROM SAID MAIN BEAM FIN EASY INSERTION THEREIN OF THE LOCKING TONGUE, SAID MAIN BEAM AND CROSS T''S HAVING HANGERS, HOLES FORMED THEREIN FROM WHICH EXTEND WIRE HANGERS, EACH TONGUE HAVING A LOCKING HOLE FORMED THEREIN, A LOCKING DIMPLE FORMED IN THE CENTRAL FIN OF SAID MAIN BEAMS WHICH REGISTERS WITH AND SNAPS INTO SAID LOCKING HOLES WHEN THE LOCKING TONGUE IS FULLY INSERTED INTO ITS ASSOCIATED HOLDING TABS, AND A STOP LUG PROJECTING FROM THE CENTRAL FIN OF SAID MAIN BEAMS, EACH TONGUE HAVING A STOP LUG TO AID IN POSITIONING SAID TONGUE IN ITS FULLY INSERTED POSITION. 